Potterton Profile 80eL

[tedjyg]

I have a problem, the Boiler fires up OK and the system runs until the Boiler reaches the set Temperature. When the Boiler cools down and tries to re-ignite it seems to go into a loop ie It goes through the motions but doesn't actually fire-up. At this time I hasten to add the the pilot is alight, and looking through the inspection window the pilot flame appears to distort when I assume the main Gas valve is in operation, but doesn't ignite. It then seems to repeat the procedure but no ignition.
I can get the Boiler to ignite if I either turn the Boiler stat off and then back on again or by turning the hot water and central heating request off and on, on the programmer.

I would appreciate any help with this. Thank you for your interest.
Ted

 

[Agile]

It is difficult for me to guess exactly what is wrong with your boiler although you have given a good description.

Its possible the second stage gas valve solenoid is intermittent although that would not explain why you seem to be able to get it to ignite using external controls sequences which in reality have no effect on the boiler itself. Could also be the PCB at fault.

As the problem seems combustion related then the usual advice would be to get a competent CORGI to diagnose the fault.

Tony

 

[Nixt]

Had these symptoms on a Halstead (semi-permanent pilot version), which turned out to be a partially blocked pilot injector.

 

[Agile]

But Nixt that would cause no flame to be detected and it would then carry on sparking.

This case implies that the sparking stops because a flame has been detected.

Tony

 

[ChrisR]

Tedjyg didn't mention sparking, but it can be quite quiet on these.
Several pointers to an inadequate pilot there
Get it serviced!
The pcb's do go intermittent quite often too, unnoticed until something else needs attention.

 

[Nixt]

But Nixt that would cause no flame to be detected and it would then carry on sparking.

This case implies that the sparking stops because a flame has been detected.

Tony

The pilot did establish (only partial blockage) eventually which did stop the sparking but I seem to remember it firing full burner intermittently, as the OP described on theirs. However it's only a suggestion. The only semi-pilots I've ever installed are Ideal Classics, so no great experience.

 

[tedjyg]

Many thanks for your advice.
Ted